Abstract: Since 2006, the water level in Huanghua well appears sudden rising changes several times along with synchronous or hysteretic dropping of water temperature.Load-unload test of water level and temperature gradient surveying are done and the hydrogeological condition of the well are studied.The result shows that water level rising is mostly caused by external environment influence, water temperature synchronous or hysteretic dropping is its secondary effect;infiltration of cold water is more reasonable cause.